Difforum · Glitch (DSP databending)

If Datamosh is the motion-melt glitch, Difforum · Glitch (DSP databending) is the everything-else glitch: a one-stop IMAGE-batch node that stacks the full vocabulary of digital damage - convolution kernels, a 1D delay-line databender, bitcrushing, VHS jitter and banding, chroma blur, and RGB channel split. It's the node you reach for when you want your clip to look like it survived a damaged CRT feed, a broken JPEG pipeline, or a signal that's been through seven effects pedals. Works on a single image, a feedback render, or whole footage batches.

Everything defaults to 0/off, so it's an additive toolbox: turn on only what you want, stack as many as you like. The inputs, grouped by flavor:

• Kernel pass - kernel (none/blur/sharpen/edge/emboss) with a kernel_mix (0–1) controlling how much of the convolved result blends over the original. Edge + emboss give that "image processed through a broken scanner" texture.
• dsp_delay + dsp_feedback - the databending pair. A 1D delay line reads the image data (row-major, like a signal) and feeds part of it back: dsp_delay is the line length in samples (0–500k, stepped by 64 - think bytes of the image stream), dsp_feedback (0–0.95) how much loops back. This is the true databend - it smears the image along its own data layout rather than across spatial coordinates. This is the pair to play with last; it's the most unpredictable and the most authentically "databend."
• bitcrush (0–7) - quantize the color depth for that harsh digital staircase banding. 1–3 is subtle crunch, 6–7 is brutally posterized.
• VHS trio - vhs_jitter (0–64, horizontal line displacement), vhs_band (0–1, tracking-band strength), chroma_blur (0–31, color-channel smearing). Together: the tape-deck look.
• rgb_split (0–64) - chromatic aberration, channel separation in pixels. The cheapest way to sell "broken display" in any amount.
• seed (optional) - makes the jitter deterministic, which you want on video so the glitch doesn't re-roll into seizure flicker every frame.

Output: frames (IMAGE batch), same length in/out. This node loves the VJ pipeline - Load Video → grade → Glitch → Echo Trails → Save Video is a complete broken-tape aesthetic in a handful of nodes, no checkpoint required.

Install

cd ComfyUI/custom_nodes
git clone https://github.com/chillithebillis/Difforum.git difforum

Restart ComfyUI ([Difforum] loaded N nodes) or ComfyUI Manager → "Difforum". numpy-only, no model downloads.

Common issues

• "Where do I even start?" One dial at a time. rgb_split at 8 + vhs_jitter at 12 + vhs_band at 0.3 is an instantly recognizable VHS look with three clicks. Add bitcrush later.
• The dsp pair does something horrifying. Yes - that's the point, but it's also the least predictable. Start with a big dsp_delay (long line, less global smearing) and small dsp_feedback; the texture of the effect depends on image width, so expect to fiddle.
• Flickering chaos on video. vhs_jitter without a fixed seed re-rolls per frame. Set the seed for a stable (but still glitchy) tape.

Honest verdict: it's a toy until it isn't. Most of these effects you'd reach for once a month; the VHS + RGB combo is good enough that it's the difference between "processed clip" and "found footage," and it costs zero models and almost zero compute.